System and method for abstracting sata and/or sas storage media devices via a full duplex queued command interface to increase performance, lower host overhead, and simplify scaling storage media devices and systems

ABSTRACT

A simplified host accesses SATA and SAS storage media devices by abstracting the SATA and SAS protocols with one full duplex protocol that supports full command queuing to each storage media device, whether SATA or SAS, where the abstraction protocol is performance-centric and supports common high-level read and write access to a pool of storage media devices, each of which may have a SATA or SAS interface. The abstraction protocol is link-agnostic and may be carried via a multiplicity of direct attach or networked interfaces, including but not limited to PCIe, Ethernet (e.g., 1 GbE, 10 GbE, 40 GbE, or 100 GbE), Infiniband, ThunderBolt, Firewire, USB, and/or custom interfaces. The abstraction protocol also supports communicating with port expanders and port multipliers.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates generally to the field of storage devices.More specifically, the present invention is related to a system andmethod for abstracting SATA and/or SAS storage media devices via a fullduplex queued command interface to increase performance, lower hostoverhead, and simplify scaling storage media devices and systems.

2. Discussion of Related Art

The present state of the art for directly interfacing to a storage mediadevice (rotational hard drive, solid state drive, ram drive, etc.) is touse interface protocols such as SATA (Serial ATA, where ATA=AdvancedTechnology Attachment) or SAS (Serial Attached SCSI). Both of theseinterfaces are rooted in much older parallel interfaces (PATA and SCSI).The general protocols remain unchanged from the original parallelspecifications, they are simply now transported via serial interfacerather than shared access bidirectional parallel busses. In the case ofSATA, this limits the high-speed full duplex serial link to effectivelyhalf duplex as full command queuing and out of order responses are notnatively supported. While Native Command Queuing (NCQ) is supported by asubset of SATA storage media devices, it only addresses some datatransfers, not all commands and typically does not support interleavingread and write commands. SAS supports Tagged Command Queuing (TCQ) toovercome some of these limitations with SATA. The host must support andmanage both protocols when accessing a mixture of devices (some SATA,some SAS). The host software layers interfacing to SATA or SAS mustsupport their high protocol overhead.

SATA may have a Port Multiplier and SAS may have a Port Expander. Eachof these devices split an exiting SATA or SAS link, respectively, intoadditional ports. Either SATA or SAS protocol is the path into thesedevices from the host, thus the host still must deal with SATA or SAS.In addition, this link bandwidth between the Multiplier/Expander and thehost is shared across the storage media devices downstream. SATA PortMultipliers are typically used to increase storage capacity, subdividingthe bandwidth between the controller and the Port Multiplier. SATA PortMultipliers cannot be cascaded, limiting the amount of increased storagecapacity. Furthermore, not all SATA controllers support PortMultipliers. SAS Port Expanders may also be used to increase storagecapacity, however, also allow several SAS links to the host to begrouped together (ganged) as one port to increase bandwidth between thecontroller and the Port Multiplier as well. It is possible for a SASinterface to carry SATA via SAS-STP (SAS SATA-Transport-Protocol).

In prior art, as depicted in FIG. 1, the host computer or processingelement 100 supports SATA and/or SAS as a means to communicate with SATAstorage media devices (SATA SMD) 106 & 110 and SAS storage media devices(SAS SMD) 108, respectively. The physical interface to the SMDs is madevia a SATA controller 102 or SAS controllers 104 and 105, eachcommunicating with SMDs via a serial interface. A SAS controller is ableto interface with a SAS SMD (e.g., SAS controller 104 interfacing withSAS SMD 108) as well as a SATA SMD (e.g., SAS controller 105 interfacingwith SATA SMD 110), where SATA SMD is supported by the SAS-STP (SASSATA-Transport-Protocol). A SATA controller is able to interface only toa SATA SMD (i.e., SATA controller 102 is able to interface only to SATASMD devices like SATA SMD 106).

Optionally, as shown in FIG. 2, a SATA controller 202 may interface to aport multiplier 204 to connect to one or more SATA SMDs. Likewise, a SAScontroller 206 may interface to a port expander 208 to connect to one ormore SAS SMDs or SATA SMDs.

However, prior art systems such as the ones described above do notprovide a system and method for abstracting SATA and/or SAS storagemedia devices via a full duplex queued command interface to increaseperformance, lower host overhead, and simplify scaling storage mediadevices and systems. Embodiments of the present invention are animprovement over prior art systems and methods.

SUMMARY OF THE INVENTION

In one embodiment, the present invention provides for a routablepacket-switched network supported by an abstraction protocol comprising:at least one host; a master controller, the master controller comprisinga master processing element, an optional master memory, a mastercontroller interface to communicate with the host, and at least onemaster controller control link interface; and at least one edgecontroller, the edge controller comprising an edge processing element,an optional edge memory, an edge controller control link interface tocommunicate with the master controller via the master controller controllink interface, a SATA port multiplier communicating with a plurality offirst storage media devices via the SATA protocol, and a SAS portexpander communicating with a plurality of second storage media devicesvia the SAS protocol, wherein the master controller and the edgecontroller communicate via the abstraction protocol, the abstractionprotocol simultaneously supporting both serial ATA (SATA) and serialattached SCSI (SAS) storage media devices, the abstraction protocolcomprising a full-duplex protocol supporting full command queuing forthe first and second storage media devices.

In another embodiment, the present invention provides for a routablepacket-switched network supported by an abstraction protocol comprising:at least one host; a master controller, the master controller comprisinga master processing element, a master controller interface tocommunicate with the host, and at least one master controller controllink interface; and at least one edge controller, the edge controllercomprising an edge processing element, an optional edge memory, an edgecontroller control link interface to communicate with the mastercontroller via the master controller control link interface, a portmultiplier communicating with a plurality of storage media devices,wherein the master controller and the edge controller communicate viathe abstraction protocol, the abstraction protocol comprising afull-duplex protocol supporting full command queuing for the storagemedia devices.

In another embodiment, the present invention provides for a routablepacket-switched network supported by an abstraction protocol comprising:at least one host; a master controller, the master controller comprisinga master processing element, a master controller interface tocommunicate with the host, and at least one master controller controllink interface; and at least one edge controller, the edge controllercomprising an edge processing element, an optional edge memory, an edgecontroller control link interface to communicate with the mastercontroller via the master controller control link interface, and a portexpander communicating with a plurality of storage media devices,wherein the master controller and the edge controller communicate viathe abstraction protocol, the abstraction protocol comprising afull-duplex protocol supporting full command queuing for the storagemedia devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure, in accordance with one or more various examples,is described in detail with reference to the following figures. Thedrawings are provided for purposes of illustration only and merelydepict examples of the disclosure. These drawings are provided tofacilitate the reader's understanding of the disclosure and should notbe considered limiting of the breadth, scope, or applicability of thedisclosure. It should be noted that for clarity and ease of illustrationthese drawings are not necessarily made to scale.

FIG. 1 illustrates a prior art host communicating with a SATA and SAScontrollers via SATA, SAS, or SAS-STP protocol.

FIG. 2 illustrates a prior art SATA controller communicating with a SATAport multiplier and a SAS controller communicating with a SAS expander.

FIG. 3 illustrates one example of the present invention's mastercontroller communicating with a host and edge controllers.

FIG. 4A through 4C illustrate various non-limiting examples of thepresent invention's edge controller.

FIGS. 5A and 5B illustrate a system level overview of non-limitingexamples of the present invention's master controller interacting withone edge controller that is communication with storage media devices andanother edge controller that is in communication with other edgecontrollers and other storage media devices.

FIG. 6 illustrates the present invention's edge controller that is ableto communicate with either a SATA port multiplier or a SAS portexpander, or both.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While this invention is illustrated and described in a preferredembodiment, the invention may be produced in many differentconfigurations. There is depicted in the drawings, and will herein bedescribed in detail, a preferred embodiment of the invention, with theunderstanding that the present disclosure is to be considered as anexemplification of the principles of the invention and the associatedfunctional specifications for its construction and is not intended tolimit the invention to the embodiment illustrated. Those skilled in theart will envision many other possible variations within the scope of thepresent invention.

Note that in this description, references to “one embodiment” or “anembodiment” mean that the feature being referred to is included in atleast one embodiment of the invention. Further, separate references to“one embodiment” in this description do not necessarily refer to thesame embodiment; however, neither are such embodiments mutuallyexclusive, unless so stated and except as will be readily apparent tothose of ordinary skill in the art. Thus, the present invention caninclude any variety of combinations and/or integrations of theembodiments described herein.

This invention simplifies a host that accesses SATA and SAS storagemedia devices by abstracting the SATA and SAS protocols with one fullduplex protocol that supports full command queuing to each storage mediadevice, whether SATA or SAS. The invention is comprised of both hardware(system—architecture) and software (method—abstraction protocol). Thesimplified abstraction protocol provides high-level access commands tostorage media devices. A high-level command may ultimately resolve toseveral commands at the SATA or SAS interface, allowing the host toissue and track fewer commands. An example of which is moving a largeramount of data with one command than the SATA or SAS protocols supportnatively. The storage media devices' SATA or SAS interfaces are pushedto the edge, away from the host and toward the storage media device forwhich it supports. Pushing the SAS/SATA protocol to the edge simplifiesthe host/controller since it does not implement the legacy SAS/SATAprotocol, it can do what fits its application best. Because SAS/SATA arepushed to the edge and abstracted to the host, SATA and SAS can becomingled without impacting the host (host is SAS/SATA-agnostic). Evenwhen SATA is tunneled over SAS (STP) the host is using the SATA/STPprotocol. The host generally need not be aware of storage media devices'interface protocol during operation. Furthermore, recoverable storagemedia device errors, such as retries, may be handled at the edge, localto the storage media device, offloading the task from the host. In theevent data duplication is desired, this also may be handled at the edge,offloading the task from the host. This offload may be important withSATA if NCQ is to be used, as any remaining queued read or writecommands will be flushed if an error occurs, requiring those commands tobe re-issued. The abstraction protocol supports flow control between thehost and the edge. Since SATA and SAS handle flow control differently,this storage media device flow control is dealt with at the edge ratherthan placing the burden on the host.

This abstraction protocol is performance-centric and supports commonhigh-level read and write access to a pool of storage media devices,each of which may have a SATA or SAS interface. The abstraction protocolis link-agnostic and may be carried via a multiplicity of direct attachor networked interfaces, including but not limited to PCIe, Ethernet(e.g., 1 GbE, 10 GbE, 40 GbE, or 100 GbE), Infiniband, USB, ThunderBolt,Firewire, and/or custom interfaces. The abstraction protocol linkbandwidth need not be related to the bandwidth of the individual storagemedia devices' SATA or SAS interface. The data being written to or readfrom a storage media device may be pushed by the source or may be pulledby the destination. For example, when the link is Ethernet it istypically best to send the bulk data along with the command packet incase of write and along with the response packet in the case of read(pushed). When the link is PCIe it is typically best that the bulk databe retrieved separately from issuing a command or response, when thecommand is ready to execute or a response is received (pulled).

The abstraction protocol supports packet-switched routable fabric anderror recovery. Routing may be based on logical address, WWN (World WideNumber—a unique global ID number), or physical address. Logical addressor WWN may be mapped to a physical address (e.g. by table lookup). Thismapping may be static or dynamically updated based upon a discoveryprocess as storage media devices are (i) inserted or removed from thesystem and/or (ii) powered on or off.

A master controller 304, as depicted in FIG. 3, contains (i) one or moremaster processing elements 306 that carries out the processing of themaster side of the abstraction protocol and communicates with at leastone host 302 via a master controller interface 308 connected to the host302 by a host link 320 and (ii) one or more control link interfaces 310through 312, which communicate with one or more edge controllers 316through 318 via control links 320 and 322. The master controller 304 mayoptionally have its own master memory 314 for use by the functionscontained within for processing, buffering, queuing, and the like. Themaster memory 314 may be internal to the Master Controller 304 orexternal, comprised of SRAM, DRAM, RLDRAM, FLASH, or a combinationthereof. Together, the host 302, the master controller 304, and edgecontrollers 316 through 318 form a routable packet-switched networksupported by an abstraction protocol. It is possible that one or morehosts, master controllers, and/or edge controllers exist in the samephysical device, such as Field Programmable Gate Array (FPGA) orApplication Specific Integrated Circuit (ASIC), or different devices inany combination. The host link 320 may be implemented with adirectly-addressable memory interface, Universal Serial Bus (USB),Ethernet, Peripheral Component Interconnect Express (PCIe), Infiniband,ThunderBolt, Firewire, and/or other common or custom interconnecttechnologies. The control links 320 & 322 may also be implemented with adirectly-addressable memory interface, USB, Ethernet, PCIe, Infiniband,ThunderBolt, Firewire, and/or other common or custom interconnecttechnologies. Each of the host link 320 and control links 320 & 322 maybe implemented with different interconnect technologies, they need notbe the same. For example the host link 320 may be implemented with PCIewhile the control links 320 & 322 may be implemented with 10 GbEthernet.

FIG. 4A depicts a non-limiting example of an edge controller. The edgecontroller 402 contains (i) one or more edge processing elements 404that carries out the processing of the edge side of the abstractionprotocol and communicates with one or more master controllers 406 & 408via control link interfaces 410 & 412 communicating with a mastercontrollers 406 & 408 via control links 414 & 416; (ii) one or more SMDinterfaces 418 & 420 which communicate with one or more SMDs 422 & 424via SATA and/or SAS links 426 and 428; (iii) optionally, one or moreforward link interfaces 430 communicating with other edge controllers432 via control links 448 used to forward those abstract protocolpackets from master controllers 406 or 408 (received via control linkinterfaces 410 & 412 that are not destined for the edge controller 402that received them) to another edge controller 432; and (iv) optionally,one or more master controllers 434 & 436 communicating with other edgecontrollers 438 & 440 via control links 442 & 444 when an edgeprocessing element 404 wishes to author abstract protocol messages toother edge controllers 438 & 440. A forward link interface 430 may befunctionally equivalent to a control link interface 410 & 412 in certainembodiments. An edge controller 402 may optionally have its own edgememory 446 for use by the functions contained within for processing,buffering, queuing, and the like. The edge memory 446 may be internal tothe Edge Controller 402 or external, comprised of SRAM, DRAM, RLDRAM,FLASH, or a combination thereof. It is possible that multiple edgecontrollers share the same edge memory when physical proximity of edgecontrollers allows for such sharing. It is also possible that the edgememory and master memory associated with a master controller may becombined into one when physical proximity of a master controller and anedge controller allow for such combining.

FIG. 4B depicts another non-limiting example of an edge controller thatacts as a forwarding/routing device. The edge controller 474 contains(i) one or more edge processing elements 460 that carries out theprocessing of the edge side of the abstraction protocol and communicateswith one or more master controllers 448 & 450 via control linkinterfaces 456 & 458 communicating with a master controllers 448 & 450via control links 452 & 454; and (ii) one or more master controllers 462& 468 communicating with other edge controllers 466 & 472 via controllinks 464 & 472 when an edge processing element 460 wishes to authorabstract protocol messages to other edge controllers 466 & 472. Itshould be noted that in this embodiment, edge controller 474 acts as aforwarding/routing device as there are no storage media devicesconnected to it. An edge controller 474 may optionally have its own edgememory 476 for use by the functions contained within for processing,buffering, queuing, and the like. The edge memory 476 may be internal tothe Edge Controller 474 or external, comprised of SRAM, DRAM, RLDRAM,FLASH, or a combination thereof. It is possible that multiple edgecontrollers share the same edge memory when physical proximity of edgecontrollers allows for such sharing. It is also possible that the edgememory and master memory associated with a master controller may becombined into one when physical proximity of a master controller and anedge controller allow for such combining.

FIG. 4C depicts another non-limiting example of an edge controller,which is a variation of the edge controller shown in FIG. 4A. The edgecontroller 402′ contains (i) one or more edge processing elements 404′that carries out the processing of the edge side of the abstractionprotocol and communicates with one or more master controllers 406′ &408′ via control link interfaces 410′ & 412′ communicating with a mastercontrollers 406′ & 408′ via control links 414′ & 416′; (ii) one or moreSMD interfaces 418′ & 420′ which communicate with one or more SMDs 422′& 424′ via SATA and/or SAS links 426′ and 428′; (iii) optionally, one ormore forward link interfaces 430′ communicating with another edgecontroller 432′ via control links 448′ used to forward those abstractprotocol packets from master controllers 406′ or 408′ (received viacontrol link interfaces 410′ & 412′ that are not destined for the edgecontroller 402′ that received them) to another edge controller 432′; and(iv) optionally, one or more master controllers 434′ & 436′, mastercontroller 434′ communicating with edge controller 432′ over controllink 442′ and master controller 436′ communicating with edge controllers440′ via control links 444′ when an edge processing element 404′ wishesto author abstract protocol messages to edge controllers 432′ and/or440′. A forward link interface 430′ may be functionally equivalent to acontrol link interface 410′ & 412′ in certain embodiments. An edgecontroller 402′ may optionally have its own edge memory 446′ for use bythe functions contained within for processing, buffering, queuing, andthe like. The edge memory 446′ may be internal to the edge controller402′ or external, comprised of SRAM, DRAM, RLDRAM, FLASH, or acombination thereof. It is possible that multiple edge controllers sharethe same edge memory when physical proximity of edge controllers allowsfor such sharing. It is also possible that the edge memory and mastermemory associated with a master controller may be combined into one whenphysical proximity of a master controller and an edge controller allowfor such combining. For the sake of simplicity, control links 448′ and442′ are shown as connecting individually to edge controller 432′,however, they may be combined into a single connection to EdgeController 432′ (e.g. muxed or multiplexed together).

In one embodiment, as depicted in FIG. 5A, a master controller 502communicates with one or more edge controllers 504 & 506, via controllinks 508 and 510, respectively. Edge controller 504 communicates withmultiple SMDs 512 through 514 via SATA and/or SAS links 516 & 518depending on the type of SMD (i.e., SATA or SAS). Edge controller 506communicates with multiple SMDs 520 through 522 via SATA and/or SASlinks 524 & 526 depending on the type of SMD (i.e., SATA or SAS), aswell as communicating with two other edge controllers 528 and 530. Edgecontroller 528 communicates with the edge controller 506 via a forwardlink interface 532 and control link 534. In this case, abstractionprotocol packets from master controller 502 may be forwarded or proxy toanother edge controller 528 based on certain criteria, including but notlimited to, broadcast or destination that is not local to EdgeController 506. Another edge controller 530 communicates with edgecontroller 506 via master controller 536 and control link 538. In thiscase, edge controller 506 may be servicing an abstraction protocolcommand in which some action is required at edge controller 506 as wellas some action at a different edge controller 530, this includessplitting on abstraction protocol command into multiple abstractionprotocol commands each destined for one or more other edge controllers530. Edge controller 528 communicates with multiple SMDs 540 & 542 viaSATA and/or SAS links 544 & 546 depending on the type of SMD (i.e., SATAor SAS). Edge controller 530 communicates with multiple SMDs 548 & 549via SATA and/or SAS links 550 & 552 depending on the type of SMD (i.e.,SATA or SAS). A multiplicity of control links 508, 510, 534, and 538 maybe implemented with the same or different interconnect technology,including but not limited to directly-addressable memory interface, USB,Ethernet, PCIe, Infiniband, Thunderbolt, and/or Firewire. In certaincases, such as Ethernet, each Control Link 508, 510, 534, and/or 538 maybe the same network.

In another embodiment, as depicted in FIG. 5B, a master controller 502communicates with one or more edge controllers 504′ & 506′, via controllinks 508′ and 510′, respectively. Edge controller 504′ communicateswith multiple SMDs 512′ through 514′ via SATA and/or SAS links 516′ &518′ depending on the type of SMD (i.e., SATA or SAS). Edge controller506′ communicates with multiple SMDs 520′ through 522′ via SATA and/orSAS links 524′ & 526′ depending on the type of SMD (i.e., SATA or SAS),as well as communicating with two other edge controllers 528′ and 530′.Edge controller 528′ communicates with the edge controller 506′ via aforward link interface 532′ and control link 534′. In this case,abstraction protocol packets from master controller 502′ may beforwarded or proxy to another edge controller 528′ based on certaincriteria, including but not limited to, broadcast or destination that isnot local to edge controller 506′. Edge controller 506′ communicateswith edge controller 528′ via master controller 536′ and control link538′. Edge controller 506′ may be servicing an abstraction protocolcommand in which some action is required at edge controller 506′ as wellas some action at a different edge controller 528′, this includessplitting on abstraction protocol command into multiple abstractionprotocol commands each destined for at least one additional edgecontrollers 528′. Edge controller 528′ communicates with multiple SMDs540′, 542′, 548′, and 549′ via SATA and/or SAS links 544′, 546′, 550′,or 552′ depending on the type of SMD (i.e., SATA or SAS). A multiplicityof control links 508′, 510′, 534′, and 538′ may be implemented with thesame or different interconnect technology, including but not limited todirectly-addressable memory interface, USB, Ethernet, PCIe, Infiniband,Thunderbolt, and/or Firewire. In certain cases, such as Ethernet, eachControl Link 508′, 510′, 534′, and/or 538′ may be the same network. Forthe sake of simplicity, Control Links 534′ and 538′ are shown asconnecting individually to Edge Controller 528′, however, they may becombined into a single connection to Edge Controller 528′ (e.g. muxed ormultiplexed together).

In another embodiment, as depicted in FIG. 6, an edge controller 602communicates with a SAS port expander 606, which then communicates withone or more SAS and or SATA SMDs 616 through 620. Edge controller 602may also communicate with a SATA port multiplier 604 via a SATA link608, which then communicates with one or more SATA SMDs 612 through 614.

While FIG. 6 depicts both a port multiplier 604 and a port expander 606,it should be noted that embodiments with just a port multiplier and justa port expander are within the scope of the invention.

For example, in one embodiment, the present invention provides for aroutable packet-switched network supported by an abstraction protocolcomprising: at least one host; a master controller, the mastercontroller comprising a master processing element, an optional mastermemory, a master controller interface to communicate with the host, andat least one master controller control link interface; and at least oneedge controller, the edge controller comprising an edge processingelement, an optional edge memory, an edge controller control linkinterface to communicate with the master controller via the mastercontroller control link interface, a port multiplier communicating witha plurality of storage media devices, wherein the master controller andthe edge controller communicate via the abstraction protocol, theabstraction protocol comprising a full-duplex protocol supporting fullcommand queuing for the storage media devices.

In another embodiment, the present invention provides for a routablepacket-switched network supported by an abstraction protocol comprising:at least one host; a master controller, the master controller comprisinga master processing element, an optional master memory, a mastercontroller interface to communicate with the host, and at least onemaster controller control link interface; and at least one edgecontroller, the edge controller comprising an edge processing element,an optional edge memory, an edge controller control link interface tocommunicate with the master controller via the master controller controllink interface, and a port expander communicating with a plurality ofstorage media devices, wherein the master controller and the edgecontroller communicate via the abstraction protocol, the abstractionprotocol comprising a full-duplex protocol supporting full commandqueuing for the storage media devices.

For the sake of simplicity, the system is described as being within achassis, it should be noted that the entire system need not beco-located within one chassis or physical location, as one or moreindividual elements may be located as part of a differentchassis/location.

The above-described features and applications can be implemented assoftware processes that are specified as a set of instructions recordedon a computer readable storage medium (also referred to as computerreadable medium). When these instructions are executed by one or moreprocessing element(s) (e.g., one or more processors, cores ofprocessors, or other processing elements), they cause the processingelement(s) to perform the actions indicated in the instructions.Embodiments within the scope of the present disclosure may also includetangible and/or non-transitory computer-readable storage media forcarrying or having computer-executable instructions or data structuresstored thereon. Such non-transitory computer-readable storage media canbe any available media that can be accessed by a general purpose orspecial purpose computer, including the functional design of any specialpurpose processor. By way of example, and not limitation, suchnon-transitory computer-readable media can include flash memory, RAM,ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storageor other magnetic storage devices, or any other medium which can be usedto carry or store desired program code means in the form ofcomputer-executable instructions, data structures, or processor chipdesign. The computer readable media does not include carrier waves andelectronic signals passing wirelessly or over wired connections.

Computer-executable instructions include, for example, instructions anddata which cause a general purpose computer, special purpose computer,or special purpose processing device to perform a certain function orgroup of functions. Computer-executable instructions also includeprogram modules that are executed by computers in stand-alone or networkenvironments. Generally, program modules include routines, programs,components, data structures, objects, and the functions inherent in thedesign of special-purpose processors, etc. that perform particular tasksor implement particular abstract data types. Computer-executableinstructions, associated data structures, and program modules representexamples of the program code means for executing steps of the methodsdisclosed herein. The particular sequence of such executableinstructions or associated data structures represents examples ofcorresponding acts for implementing the functions described in suchsteps.

A computer program (also known as a program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, declarative orprocedural languages, and it can be deployed in any form, including as astand-alone program or as a module, component, subroutine, object, orother unit suitable for use in a computing environment. A computerprogram may, but need not, correspond to a file in a file system. Aprogram can be stored in a portion of a file that holds other programsor data (e.g., one or more scripts stored in a markup languagedocument), in a single file dedicated to the program in question, or inmultiple coordinated files (e.g., files that store one or more modules,sub programs, or portions of code). A computer program can be deployedto be executed on one computer or on multiple computers that are locatedat one site or distributed across multiple sites and interconnected by acommunication network.

These functions described above can be implemented in digital electroniccircuitry, in computer software, firmware or hardware. The techniquescan be implemented using one or more computer program products. Theprocesses and logic flows can be performed by one or more programmableprocessors and by one or more programmable logic circuitry. General andspecial purpose computing devices and storage devices can beinterconnected through communication networks.

Some implementations include electronic components, for examplemicroprocessors, storage and memory that store computer programinstructions in a machine-readable or computer-readable medium(alternatively referred to as computer-readable storage media,machine-readable media, or machine-readable storage media). Someexamples of such computer-readable media include RAM, ROM, read-onlycompact discs (CD-ROM), recordable compact discs (CD-R), rewritablecompact discs (CD-RW), read-only digital versatile discs (e.g., DVD-ROM,dual-layer DVD-ROM), a variety of recordable/rewritable DVDs (e.g.,DVD-RAM, DVD-RW, DVD+RW, etc.), flash memory (e.g., SD cards, mini-SDcards, micro-SD cards, etc.), magnetic or solid state hard drives,read-only and recordable Blu-Ray® discs, ultra density optical discs,any other optical or magnetic media, and floppy disks. Thecomputer-readable media can store a computer program that is executableby at least one processing element and includes sets of instructions forperforming various operations. Examples of computer programs or computercode include machine code, for example is produced by a compiler, andfiles including higher-level code that are executed by a computer, anelectronic component, or a microprocessor using an interpreter.

While the above discussion primarily refers to microprocessor ormulti-core processors that execute software, some implementations areperformed by one or more integrated circuits, for example applicationspecific integrated circuits (ASICs) or field programmable gate arrays(FPGAs). In some implementations, such integrated circuits executeinstructions that are stored on/within the circuit itself. In someimplementations, such as with FPGAs, software may be used to describehardware circuits, an example of which are FPGA programming files. SuchFPGA programming files may also include computer programs, machine code,microcode, firmware, and other software. The FPGA programming files maybe stored within an FPGA, ASIC, computer-readable storage media,machine-readable media, or machine-readable storage media.

As used in this specification and any claims of this application, theterms “computer”, “server”, “processor”, and “memory” all refer toelectronic or other technological devices. These terms exclude people orgroups of people. For the purposes of the specification, the termsdisplay or displaying means displaying on an electronic device. As usedin this specification and any claims of this application, the terms“computer readable medium” and “computer readable media” are entirelyrestricted to tangible, physical objects that store information in aform that is readable by a computer. These terms exclude any wirelesssignals, wired download signals, and any other ephemeral signals.

Those of skill in the art will appreciate that other embodiments of thedisclosure may be practiced in network computing environments with manytypes of computer system configurations, including personal computers,hand-held devices, multi-processor systems, ASIC-based systems,FPGA-based systems, microprocessor-based or programmable consumerelectronics, network PCs, minicomputers, mainframe computers, and thelike. Embodiments may also be practiced in distributed computingenvironments where tasks are performed by local and remote processingdevices that are linked (either by hardwired links, wireless links, orby a combination thereof) through a communications network. In adistributed computing environment, program modules may be located inboth local and remote memory storage devices.

It is understood that any specific order or hierarchy of steps in theprocesses disclosed is an illustration of example approaches. Based upondesign preferences, it is understood that the specific order orhierarchy of steps in the processes may be rearranged, or that allillustrated steps be performed. Some of the steps may be performedsimultaneously. For example, in certain circumstances, multitasking andparallel processing may be advantageous. Moreover, the separation ofvarious system components illustrated above should not be understood asrequiring such separation, and it should be understood that thedescribed program components and systems can generally be integratedtogether in a single software product or packaged into multiple softwareproducts.

Various modifications to these aspects will be readily apparent, and thegeneric principles defined herein may be applied to other aspects. Thus,the claims are not intended to be limited to the aspects shown herein,but is to be accorded the full scope consistent with the languageclaims, where reference to an element in the singular is not intended tomean “one and only one” unless specifically so stated, but rather “oneor more.” Unless specifically stated otherwise, the term “some” refersto one or more. Pronouns in the masculine (e.g., his) include thefeminine and neuter gender (e.g., her and its) and vice versa. Headingsand subheadings, if any, are used for convenience only and do not limitthe subject technology.

A phrase, for example, an “aspect” does not imply that the aspect isessential to the subject technology or that the aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations. Aphrase, for example, an aspect may refer to one or more aspects and viceversa. A phrase, for example, a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurations,or one or more configurations. A phrase, for example, a configurationmay refer to one or more configurations and vice versa.

The various embodiments described above are provided by way ofillustration only and should not be construed to limit the scope of thedisclosure. Those skilled in the art will readily recognize variousmodifications and changes that may be made to the principles describedherein without following the example embodiments and applicationsillustrated and described herein, and without departing from the spiritand scope of the disclosure.

While this specification contains many specific implementation details,these should not be construed as limitations on the scope of anyinvention or of what may be claimed, but rather as descriptions offeatures that may be specific to particular embodiments of particularinventions. Certain features that are described in this specification inthe context of separate embodiments can also be implemented incombination in a single embodiment. Conversely, various features thatare described in the context of a single embodiment can also beimplemented in multiple embodiments separately or in any suitablesubcombination. Moreover, although features may be described above asacting in certain combinations and even initially claimed as such, oneor more features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. In certain circumstances, multitasking and parallel processingmay be advantageous. Moreover, the separation of various systemcomponents in the embodiments described above should not be understoodas requiring such separation in all embodiments, and it should beunderstood that the described program components and systems cangenerally be integrated together in a single software product orpackaged into multiple software products.

As noted above, particular embodiments of the subject matter have beendescribed, but other embodiments are within the scope of the followingclaims. For example, the actions recited in the claims can be performedin a different order and still achieve desirable results. As oneexample, the processes depicted in the accompanying figures do notnecessarily require the particular order shown, or sequential order, toachieve desirable results. In certain implementations, multitasking andparallel processing may be advantageous.

CONCLUSION

A system and method has been shown in the above embodiments for theeffective implementation of a system and method for abstracting SATAand/or SAS storage media devices via a full duplex queued commandinterface to increase performance, lower host overhead, and simplifyscaling storage media devices and systems. While various preferredembodiments have been shown and described, it will be understood thatthere is no intent to limit the invention by such disclosure, butrather, it is intended to cover all modifications falling within thespirit and scope of the invention, as defined in the appended claims.For example, the present invention should not be limited bysoftware/program, computing environment, or specific computing hardware.

1. A routable packet-switched network supported by an abstractionprotocol comprising: at least one host; a master controller, the mastercontroller comprising a master processing element, a master controllerinterface to communicate with the host, and at least one mastercontroller control link interface; and at least one edge controller, theedge controller comprising an edge processing element, an edgecontroller control link interface to communicate with the mastercontroller via the master controller control link interface, a portmultiplier communicating with a plurality of first storage mediadevices, and a port expander communicating with a plurality of secondstorage media devices, wherein the master controller and the edgecontroller communicate via the abstraction protocol, the abstractionprotocol comprising a full-duplex protocol supporting full commandqueuing for the first and second storage media devices.
 2. The routablepacket-switched network of claim 1, wherein the abstraction protocolsimultaneously supports both serial ATA (SATA) and serial attached SCSI(SAS) storage media devices.
 3. The routable packet-switched network ofclaim 2, wherein a single high level command issued by the mastercontroller resolves to one or more SATA commands.
 4. The routablepacket-switched network of claim 2, wherein a single high level commandissued by the master controller resolves to one or more SAS commands. 5.The routable packet-switched network of claim 2, wherein a single highlevel command issued by the master controller resolves to one or moreSAS and one or more SATA commands.
 6. The routable packet-switchednetwork of claim 1, wherein routing between the master controller andthe edge controller is based on any of the following: logical address,world wide number (WWN), or physical address.
 7. The routablepacket-switched network of claim 5, wherein routing between the mastercontroller and the edge controller is based on the logical address thatis mapped to the physical address.
 8. The routable packet-switchednetwork of claim 7, wherein mapping between the logical address and thephysical address is updated dynamically based on a discovery process asstorage media devices are: (a) inserted; (b) removed; (c) powered on; or(d) powered off.
 9. The routable packet-switched network of claim 7,wherein routing between the master controller and the edge controller isbased on the WWN that is mapped to the physical address.
 10. Theroutable packet-switched network of claim 9, wherein mapping between theWWN and the physical address is updated dynamically based on a discoveryprocess as storage media devices are: (a) inserted; (b) removed; (c)powered on; or (d) powered off.
 11. The routable packet-switched networkof claim 1, wherein the master controller interface communicates withthe host via any of the following interfaces: direct addressable memoryinterface, USB, PCIe, Ethernet, Infiniband, ThunderBolt, or Firewire.12. A routable packet-switched network supported by an abstractionprotocol comprising: at least one host; a master controller, the mastercontroller comprising a master processing element, a master controllerinterface to communicate with the host, and at least one mastercontroller control link interface; and at least one edge controller, theedge controller comprising an edge processing element, an edgecontroller control link interface to communicate with the mastercontroller via the master controller control link interface, a portmultiplier communicating with a plurality of storage media devices,wherein the master controller and the edge controller communicate viathe abstraction protocol, the abstraction protocol comprising afull-duplex protocol supporting full command queuing for the storagemedia devices.
 13. The routable packet-switched network of claim 12,wherein the abstraction protocol supports serial ATA (SATA) storagemedia devices.
 14. The routable packet-switched network of claim 12,wherein the abstraction protocol supports serial attached SCSI (SAS)storage media devices.
 15. The routable packet-switched network of claim12, wherein a single high level command issued by the master controllerresolves to one or more SATA commands.
 16. The routable packet-switchednetwork of claim 12, wherein a single high level command issued by themaster controller resolves to one or more SAS commands.
 17. A routablepacket-switched network supported by an abstraction protocol comprising:at least one host; a master controller, the master controller comprisinga master processing element, a master controller interface tocommunicate with the host, and at least one master controller controllink interface; and at least one edge controller, the edge controllercomprising an edge processing element, an edge controller control linkinterface to communicate with the master controller via the mastercontroller control link interface, and a port expander communicatingwith a plurality of storage media devices, wherein the master controllerand the edge controller communicate via the abstraction protocol, theabstraction protocol comprising a full-duplex protocol supporting fullcommand queuing for the storage media devices.
 18. The routablepacket-switched network of claim 17, wherein the abstraction protocolsupports serial ATA (SATA) storage media devices.
 19. The routablepacket-switched network of claim 17, wherein the abstraction protocolsupports serial attached SCSI (SAS) storage media devices.
 20. Theroutable packet-switched network of claim 17, wherein a single highlevel command issued by the master controller resolves to one or moreSAS commands.